Pauflerite, β-VO(SO4), is a new mineral species from the fumaroles of the Great Fissure Tolbachik eruption (GFTE), Kamchatka Peninsula, Russia. It was found in 1977 in the first cinder cone of the North breach of the GFTE. The mineral occurs as light green prismatic crystals up to 0.1 mm in length, associated with shcherbinaite (V2O5), an unknown Tl-Bi sulfate and finely crystalline Mg, Al, Fe and Na sulfates. Paufterite is light green with a white streak and vitreous luster; the mineral is transparent and non-fluorescent. The Mohs hardness is 3-4. Pauflerite is brittle, and without visible cleavage. The density is 3.36(4) (measured) and 3.294 g/cm3 (calculated). The mineral is biaxial, optically positive, α 1.731(4), β 1.778(2), γ 1.845(4), with 2Vmeas ≈ 90°, and 2Vcalc equal to 83°. The orientation was determined as X = a; further details are unclear. Pleochroism is clear in green tones: X light green, Ybluish green, Z light green-blue. A chemical analysis with an electron microprobe gave VO2 50.40, SO3 49.